You may know this, but I thought I'd better mention changing your 15 Amp outlets to 20 Amp outlets does not give you a 20 amp circuit- not without a 20 amp breaker and, I believe, minimum 12 gauge wiring in the circuit. Besides, you will probably want your 20 amp circuits to be dedicated to your amps. Good luck!
By the way, Ed, are you saying the 2 Earthquake Cinevova amplifiers (6 total channels) are less money than the 770 (7 channels)? These are new?

Ed?

Cinenova grand 3 is 3.5k new. So I am assuming you mean 2 channels of this is what you will use with Rm40. If I am wrong and you are getting 2 amps each with 3 mono-aural channels, each weighing 120lb (ouch!)for less than the cost of one 770, give me john's number.

I think you are going to have to run this with a tube pre and not an ss pre.

I can not in good conscious say it's a good idea to put (or leave) 15 amp receptacles on 20 amp lines. You can get receptacles that don't need adapters. They're very easy to find at a major store, such as Home Depot. In all likelyhood he won't ever draw more than 15 amps at all, let alone long enough to fry the receptacle, but as long as the possibility is there he should fix it. Like I said before, it only costs a couple bucks and can save your house. That seems like a worthy investment to me.

Also, we don't know exactly what will be on the line in the next few months when he makes his purchases because he doesn't know yet. We also don't know what will happen years down the road. Don't say just upgrade then, he may not remember. Just do it right now and there are no worries.